Pelvic support osteotomy in the treatment of patients with excision arthroplasty

Abstract

Resistant hip infection in adults can be a complicated problem that does not respond to surgical and medical treatment. In such cases, the only remaining option is excision arthroplasty. This line of treatment can eradicate the infection but also is associated with poor function. In some cases, conversion of excision arthroplasty to artificial joint replacement is associated with too great a risk because of local hip surgical risks or low immunity with risk of recurrent infection. Pelvic support osteotomy with the Ilizarov modification can present an alternative solution for such patients. This study included 11 patients with resistant hip infection who were treated using excision arthroplasty. Pelvic support osteotomy then was used to improve hip stability and abductor muscle function. The Ilizarov modification was applied to correct mechanical alignment of the limb and the limb length discrepancy. Harris hip scores improved in all patients: the average score preoperatively was 43.5 (range, 31-50), whereas at final followup, the average score was 70.9 (range, 65-80). Pelvic support osteotomy, along with the Ilizarov modification, can provide an alternative treatment to improve function in patients previously managed with excision hip arthroplasty and Girdlestone surgery.

Fig. 1

The radiograph shows the pelvic support proximal femoral osteotomy with increased surface contact area between the femur and pelvis, more horizontal proximal femur, more medial center for rotation, and more distal abductor insertion. The distal femoral osteotomy is done for adjustment of mechanical axis of the limb and correction of limb length discrepancy. The line on the left side of the figure shows the proximal femoral osteotomy valgus angulation and the distal femoral osteotomy varus angulation and lengthening, and the line on the right side of the figure shows the adjustment of the mechanical axis of the femur and its 90° relation to the horizontal pelvis.

Fig. 2A–F

(A) An adduction preoperative radiograph was used for planning the level for the proximal femoral osteotomy. The lines show the horizontal line of the pelvis and its relation to the shaft of the femur in maximum adduction. The osteotomy should be at the level of the ischial tuberosity. (B) A single-limb standing radiograph was used to measure the pelvifemoral angle. The proximal femoral valgus osteotomy angulation equals this angle plus 15° for more tension on the abductor muscles. The lines show the angle between the pelvis and the femoral shaft. Early postoperative radiographs show (C) the proximal valgus femoral osteotomy and (D) the distal femoral varus osteotomy before lengthening. (E) A radiograph at the end of lengthening shows adjustment of the mechanical axis of the limb before consolidation of the new bone. (F) A long standing radiograph after removal of external fixation shows equalization of limb length and adjustment of the mechanical axis. The lines show the joint line of the knee parallel to the pelvis and to the ground.